Cut-out for electrical circuits.



N. l. CCVNHAI)A CUT-OUTFOR ELECTRICALCIHCUITS.

Patented July 1Q, 1917.

3 SHEETSSHEETI l 9 u w APPLICAT|)N FILED OCT. I6. 1915-/ N. 1. CONRAD.CUT-OUT FOR ELECTRICAL CIRCUITS.

I AP-FLICATION IFIIE!) 0CT.16, l9|5| Patented 10,

3 sniirslsnzsrz.

4To all whom z't may concern:

` Chicago, in the county of Cook and UNITED STATES PATEN OFFICE.

NICHOLQLS J'.4 CONRAD, 0F CHICAGO, ILLINOIS, ASSIGNOR TO SCHWEITZER &CONRAD, INC., OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

CUT-OUT ron ELEc'rnIcAL CiBcUITs.

Be it iknown that I, NICHOLAS J. Com-LAD, a citizen of the UnitedStates, resldln at of Illinois, have invented a certain new and i usefulImprovement in Cut-Outs for ElectricalCircuits-of whichthe following isa full,.'clear concise, and -exact description, reference'being had tothe accompanying drawings, forming a part of this specification.;,.'.'

My invention relates to cut-outs for electrical circuits. Onlinesemploying" hi h voltages,- fuses are desirable .to protect t e,apparatus and circuits just as nuchas in Y low voltage work. While inlow and mod-` erate voltage work and especially in small capacitycircuits the fuse may-be replaced while' 4voltage is` upon ltheilinewithout dantaken w or -large amounts of power Vare to be dealt with. Insuch case, especially where voltages are employed, thel fuse' cannolile-4 tion of the lower end of the fuse 'handle carrying the same;-

Fig. l is a front elevational view of-'aj replaced in. the hne whilevoltage is on without great danger totheoperator. -In small powerfworkit is common 'to 'insert a knife ,or snap "switch in the circuit andwhen a fuse is to be'replaced the-switchl is opened.A

0n three lphase systemsopening of one ling" uonly would be imracticable. `As a result?` -`fthe so-calle'd `cut-out has beendevelo-ped. I n general this com "rises a: swltching block or bladeremovab e fro`n`1` the .line terminals, this block or blade havingincor-4 rated therein a fusiblelinkoroonducton The .block ,inay bewithdravvn"completely' from the' line terminals in 'order'tojmspect orrepair the same without slubjectin =th`e.

operator to 4dan r from the line. vo tage. Where the fusi le linkcomprises a soft I metal conductor the construction is Vrelativelysimple, but for high lvoltages or forlarge capacity such type of fuseAcannot be' employed anda diflerentformpf f use and mounting must rbeprovlded.

tate.

vI have illustrated E? to4 the' cgierat'or,V special precautions must yere 'high voltages are employed Vof one -orm of'fused cut-out,

The cut-out, which I' shall-describe is def si ed to employ aparticularly efficient fuse o the type disclosed in the patents toEdmund O. Schweitzer and Nicholas J. ConradNos.- 1,050,493, .1,033,384and lloosaee,

but it is to bf.: understood'that any ot er suitable fuse or link may beemployed.

n is desirable that the cut-out be made` as compact as possible; thatthe structure be completel weather-proof for outdoor instal`v lations; lat the operator be suitablyprotected while' manipulatingthe device andthat a suitable indicator be rovided -for in-V dicating from the outsidet e condition of `thefuse.

The'v object of this invention is to provide a cut-Cut or. fuse 4blockwhich will embody' the above and other advantages.

In. the accompanying drawings in lwhich' an embodiment of my n-'vention- Fig. 2-is an'elevation of the same; i

Figure 15s a longitudinal vertical seccinl Fig. 3 is'a fragmentary viewof the posiand the .modified form of the invention; V

Fig. 5 is a detail view showin-g the top of the ,handle-.or mounting of``the fuse holdv; Y

Fig. 6-is a bottom plan view of the shell "or casing shown in Figs. 1and2;

Fig. 7 is'fa' fragmentaryv elevationy ofl ,a 4

fuse mounting voltages; Fig. 8 is a cross-sectional view of a form of adevicemplo'yirig a 'resistance which is inserted. in broken; and

Fig. 9 illustrates out a fuse.

'block and handle for high ai connecting -with- The lfuse 1 whichpreferabl his of the 4type y the circuit before the circuitisdisclosedin the above-men ioned patents,

comprises a glass tube 2. provided at the."

top with the cylindrical terminal 3 and at -the bottomV with asimilarterminal Ll-whic h vcontains a 'lexibleconductor 5, surrounded .by acoil spring 6and a transparent arcuextinguishing liquid 7. The terminals3 and 4 are formed in the shape of'ferrules whichy embrace the ends ofthe glass tube`2.. `I shall not4 describe this particular. type of".

fuse in detail. Suice it to say that upon blowing of the Afuse theconductor 5 is re L and the top opened so that the hot gases //ormed byblowingMmay escape from the open glass tube j.,t'hrough the vent in thesleeve and out/beneath the petticoat as is shown in-the arrowsri'nFig 1. The fuse 1 i is surrounded by an insulating shell 8 which may/lieconstructed of fiber impregnated with bakelite or the like, or anysuitable weather-proof insulating material. The top of the tube 8 isprovided with a cap or a hood 9 which closes off the open end of thetube, and forms a.V petticoat for the parts later to be described.

The upper end of the tube 8 is provided with a series of apertures 10which open into the space 11 between the hood and the tube. The gasesthat are evolved :upon blowing of the fuse 1 may escape through theapertures 10 and the space 11, and are thus diverted completely from thehands or the face of theVK operator.

A suitable sleeve 12 which comprises a metal band encircling theterminal 3 is secured upon the inside surface of the insulating tube 8and forms a stationary line terminal.

This terminal 12 is provided with a. plurality o1' spring fingers 13which are arranged to make separate yielding contact with the terminal3. The flexible lead wires 14 which are preferably stranded cables aresecured ai; the inner end to the metallic ring Y 12 and at their outerend are provided with -a suitable connector 15. The lower end of theinsulating tube,8 is surrounded by a short sleeve 16 which is securedthereto by a waterproof` joint. The lower end of the tube 8 is providedwith the metal sleeve 17 which comprises a ring of metal having thespring fingers 18 extending upwardly and embracing the terminal 1l ofthe fuse 1. The stranded cables' 19 are secured to the sleeve 17 and areconnected together to the connector 20 at their outer ends.' A metalsleeve 21 is mounted on the inside of the insulating sleeve 16 andis'secured by pins or the like to the insulatinv tube 8. The fuse 1ismounted upon arsultable. mounting block 22 which is provided with ahandle 23 at its lou er end for introducing the fuse in place in thesleeves 12 and 17.

A short cylindrical metal block ortop 2l'- is interposed between theterminal 4 of the fuse and the mounting block 22. The block 24 issecured l0 th mountingblock 22 by suitable screws 29 or the like and issecured to the terminl 4 of the fuse 1 by means of a short threaded stud25, shown in dotted lilies in Fig. 1. The/metal blocki 24. is providedwith a threaded Socket for receiving the stud 25 and is provided alsowith a small counter-bore in which lies a spring washer 28 for lockingthe parts together. A suitable guard or deflector 30 is placed betweenthe mounting block 22 and the handle 2,3. This deflector serves todeiect from the hands of the operator any gases that may escape downthrough the tube 8. It also serves to close ofi` the bottom of thesleeve 16. The metal top 24. of the mounting block 22 is provided with apair of oppositely 80'; disposed pins 31.' The pins 31 are adapted tocoperate with suitable slots to form what is known as a bayonet joint sothat when the pins 31 rest in the uppermost and inner end 32 of 85 theslots the fu'se 1 will be securely held in place in the sleeve sockets12 and 17. The sleeve 16 is provided with suitable indications 33 uponthe'outside thereof for-indicatin 1r the position which the pins 31 must9g take before the fuse can be inserted. When the p ins 4are in linewith the indications 33 they will clear the metal sleeve 21, being thenin register with the notches 34 that are formed in the metal sleeve 21.The notches 34 conununicate with a slot 35 disposed at right anglesthereto and this slotconnects with a verticallydisposed slot 36 which inturn communicatesat its upper end with the horizontally disposed slot32, above mentioned.

It can be seen that for the insertion of the Afuse 1 and mounting block22 into place it .final turn to the right and the fuse, and the blockare then firmly held in place.

If by chance the fuse should'be inserted 115 upon a line whichis'short-ircuited' there would be a tendency for the fuse, the 'mountingblock and the handle to be kicked outward out of the han'd of theoperator. To prevent this as well as to prevent dropping 12' o'fthe'fuse and mounting block I have provided'the double bayonet joints.The pins 31 are in'the'vertical portion 36 of the slot when the circuitis closed between the lower terminal 4 and` the socket. AI f the fuseblows 125 at this time, the recoil or kick will be taken up by the pins31 resting in the horizontal portion 35 of the slot.

I wish to call particular attent-ion to the fact that the top of thefuse 1, from which sleeve of insulation 42 between ing foggy `fromsmoke,

ferrule 4 enters the sleeve 17. Even if they sleeve block and handle arekicked down by explosion of the fuse, Sleeve 12 will still be in contactwhenV the pin 31 is at the end of the slot 36.

Thus there is a gas seal Ybetween the explosion orare chamber v which isformed in the top of the sleeve 8V above the fuse and the bottom of`,the device.

, A suitable mounting bracket whichepreferablyconsists of the base 37and the cap or yoke 38 provides for mounting the cut-out upon a crossarm or the like.' The main sleeve or tube 8 is provided with aperturesnear the top of the fuse and-a pair of'small" transparent'windows 39 areheld over these apertures by means of' a collaror sleeve of insulation40 so that the operator or attendant may sight through the windows 39 toascertain the condition of thefuse 1. It is to be understood that whenjthe fuse has blown the coil spring 6 and the flexible conductor will' bemoved downward and will no longer be visible through the windows 39 sothat a clear view may be had through this window. l 4

y For an-egtposed or outdoorinstallation in which thereis danger ofthewindow becomsoot'or the like, I provide a band .or sleeve 41 which islet into the sleevev40 and has an aperture cooperating withf'the opening39 which aper` 'turemay be brought into register with the opening 39 byrotating the band 41.

For especially h'igh voltages I employ a the -coperating parts ofthemounting clamp 37, 38, as

, shown'ln Fig. 4.

i minal 4 is provided with an extension ,45; leif-llglhf `s rrounds thelower end ofJthefusegand ,is

in direct contact .nal 4. 'It is' [to be'noted-"infeaehofthe forms shownthat the upper terminal 3jofltli'e fuse 1 is of'a slightlylessfd'iameter than the lower W5 i I employ van insulator' voltageinsulation, the 'handle protected by-a petticoat 43 asshown in 4 and to.secure this v 44 ofsuitable material between the mounting block 22 andthe 4handle 23. 4As shown in Figui-this insulator 44 maybe provided,witl'a plurality of `petticoats and mayinffacbconsist of a regularlineinsulator.

For high 23 is Fig..

InFig. 85 I have shown amodiiication of the fuse arrangementfin thatthelower teresi stance finaterial which with' "the annular..termiwte'rminal 4 and' the contactsleeves. 12 and` 17 the ferrule 3 andthev type' of insulation,

l 35 brings the upper terminal intoccntactjwith the sleeve causeengagement of Vsleeve".1.7. 4Upon `u are made of corresponding sizes.The nal 3 is also of greater axial length than the terminal 4 andwhenthe fuse is withdrawn from its mounting the connection will-first` bebroken between the terminal 4 and the socket 17. InY the form of.cut-out shown in Fi 8 the lowerterminal 4 of the vfusel wi leave itssocket 17 which will thenmake contact with the resistance 45,before}`the circuit is broken and thus not onlywill fthe varc which tends to beformed be lessened, but the disturbance in the circuitfoaused by breakinthe How of current will also. be less. T e resistance 45 serves as aninitial and final contact to carry the are whenthe fuse '1s' inserted orwithdrawn.` i'

If itis desired to omit the fuse 1a connecting link, such as shown inFig. 9 may-- be employed instead.,l Such a connecting link consists of abody 47 of. insulatlngrnaterial provided `with the usual terminals 3 and4 which are" connected together by a.. wire 48 or othersutableconductor' which passes through .the body y WVithsthe dummy fuse 46 thedevice operates merely as a cut-out or switch vfor opening the-circuit.

provided a yparticularly feiiicient land economical cut-out o'rfuseblo'ckwvhich.isi'protested lagainst 'disturbance 'from thel ele- It canbe seen; from theabove that JI-:hav'le ments and which isAcons'itrllic'td ftj guard'the l operatoragainst injury pins aindf thecoperatingv grooves form 4readily releas.

able` detent means for closing'the openfend of the sleeve or tubev 8'and 'for' connecting and disconnecting the' useffrom'its; sockets.,

he flexible conductors 14"' 4 or terminals.v and 19 which yconnect with,the stationary terminals give ample current. carrying capaoity but latthe same time ifo'rm' flexible leads forattachment to thefcicuitconductors. The employment of-a number oii'iexiL ible cables sideby'side to forimaronducting lead of suflicientjcapacity-allowsof-cnvenient attachment to the stationary termi- `nals,:and at 'the sametime occupies the least;

` 4 of the cutsout" -The -fuseis inserted vin two-stages, 'the vfirst.

space radially of the body stagewhen the pin is'` inA thefl-iorillontalslot 3 '0f the fuse l gether... y., i While 'I'have shownandj-describe'dmyin- 'ventionjfw-ith reference tothe15:n.titiiilarfIdetails of construction of, oneembodimeLfitis.

and with numerous.

not, the. terminal 4 with the? fthe andwhen the pinl is in theslotB21/hej1`Jfarts.. I fare4 ur properposition andare secureditotobeunderstoodthat the inventionlinay ap- -I Apear `in -diiferentforms'suggest them's'kyhs to one skilledin the art. But` I consider-"all suchmodifications and variations to be included within the spirit and scopeof my invention. What I claim is: p

1. In combination a` straight cylindrical sleeve of insulating materialadapted to bel placed in a vertical position, said sleeve having thewalls adjacent its upper end aper-V tured to form vents, an annularcontact lying against the' walls of said sleeve below said vents, acylindrical cap of insulation secured to the top of said sleeve, saidcav being undercut at said vents to form a petticoat for said vents, apluralityl of flexible stranded conductors lying side by side in theAspace between the petticoat and the sleeve and vhaving their inner endssecured to said annular contact, an open annular contact lying againstthe walls of said sleeve adja cent the lower end thereof, a cylindricalSleeve secured to the lowerend of saidrst sleeve, said latter sleeveforming a petticoat about the lower end of said .rst sleeve, saidpetticoat being recessed, a plurality of stranded `flexible conductorslying side by side insaid recess andbeing connected to said lowerannular contact,` and a cylindrical -fusehavingcontacts which areadapted'tobe embraced by said annular contact, saidlfuse ,being oranized to discharge the 'gasjes of the arc rom 'the upper end vthereof'.upon blowing, said gases being dissipated through.

said vents`in the walls of the irst sleeve.

2. In combination a straight cylindrical sleeve of--nsulating materialadapted to' be laced in a vertical position, said sleeve havlng thewalls adjacent its upper end apertured to form. vents, an annular conctsecured to thetop of said sleeve, said cap being undercut at said ventsto form a petti*v Coat for said \vents, a plurality of Aflexiblestranded conductors lying side by yside in the space' between thePetticoat and the 'sleeve and having their inner ends secured to'saidannular contact. 3. In combination ae straight' cylindrical Asleeve ofinsulating material adapted ,to be placed in a .vertical position, saidsleeve aving the walls adjacent upper end apertured to form vents, anannular contact lying against the walls o f said sleeve below -esaidvents, a cylindrical cap of insulation secured to the top of saidsleeve, said'cap being undercut at-said vents to form a petticoat forvsaid vents', a

the spacci?L between the 'Petticoat' and `the sleeve andfhaving theirInner ends secured to Suid annular contact, an open annular contact'lying againstthe walls of said sleeve adjacent the lower end thereof, acylindrical sleeve secured to the lower end of the lsaid -contact beingadapted to embrace the con-A 4ar, ljgd'nta'cts, said fuse having anormally 40 lying against the walls of said sleeve be w oldI said vents,a cylindrical cap of insula on ililg relation with said contacts,.andclosing plurality /of flexible. stranded conductors lying side by sidein rst sleeve, Vsaid latter sleeve .forrnln a petticoat about thelowerfend of said st sleeve, said petticoat being recessed, a -pluralityof stranded flexible conductors lying side by side in said recess .andbeing connected to said lower annular contact.

4. In combination a straight cylindrical sleeve of insulating materialadapted to be placed in a vertical position, said sleeve having thewalls adjacent its upperend apertured to form vents, an annular contactlying against the walls of said sleeve below said f vents, a cylindricalcap of insulation secured' to the top of said sleeve, said cap beingundercut at said vents to form a pettioats'o for said vents, a pluralityof iexible strand ed conductors lying side by side in the space; betweenthe petticoat and the sleeve and' having their inner ends secured tosaid annular contact, an open annular contact lying against the walls ofsaid sleeve adjacent the lower end, thereof, a cylindrical sleevesecured to the-lower end of the said first sleeve, said latter sleeveforming a -petticoat about the lower end .of said first sleeve, said'-petticoat being recessed, a pluralityv of l stranded flexible conductorslying side by side in said recess and being connected to l. said lowerannularcontact, said annular K 9,5; tact of a cylindrical fuse.v l' 5.In combination a cylindrical sleeve having at itsupper end a ventopening freely int' tle atmosphere, v a petticat covering said vent,lan` upper stationary contact in l0( said sleeve, a lower stationarycontact in said sle'eye 'ahd a cylindrical fuse inserted axially intdconducting relation with said stationan explosion or ar'c space abovesaid upper contact, a lower stationary contact, said contacts beingmountedl on said sleeve and in- 1 sulated from each other, lacylindricalfuse having termina-ls coperating with said ebntacts, saidfuse havingits one end\ adapte"d to be opened by blowin of the fuse,saidv fuse being inserted axial y into circuit closhe explosion o r arcspace from the opening through which the fuse is inserted. x 4 Incombination a cylindrical sleeve, an upper stationary contact mountedinv said sleeve, a lower stationary contact mounted. in said sleeve, afuse comprising a cylindg'ii. cal body .of insulation having upper andlower contact terminals', an arc extinguishing liquid in said body ofinsulation, said fuse having its lower end permanently closed i axially-1 and' closin and'having its upper end provided with a normali closedvent, a conductor within the bo y of insulation vvjonin said terminals,said fuse having means or breaking the circuit between said terminals,and simultaneously 'dischargin the gases from the upper end thereof ony, saidA cylindrical sleeve having a vent or vents freely opening ifntothe atmosphere adjacent said end of the use.

8. In combination a cylindrical-sleeve, an upper stationary contactmounted in said sleeve", a lowerstationary contact mounted .in saidsleeve, acylindrical fuse inserted ing relation to Said statioaryAContacts, Said axially', said fuse being' in current 'conductfuse havingterminal contacts Vof different diameter and having means fordischarging gases from the 'end having .thecontact of smaller diameterwhen the fuse blows, said sleeve having ventsopening freely into theatmosphere-to discharge said gases.

9. In combination a cylindrical sleeve, a

stationary cylindrical contact mounted in said'sleeve, a'seco'nd.stationary cylindrical contact, mounted ,in sa1d"'sleeve, said contactsbeing spaced vapart from each other,V

an Iincflosed cylindrical fuse having cylindrical terminals coperatingwith said sta'- tionary contacts,' sai-d'fus'c being` inserted off theupper' end front the-s ac cbelowt 'e first cylindrical sleeve `f f ingmeansfor opening one endi'thereof when n A mosphere at said end of thefuse.'

and-f ormin agas seal, the upper endof said' sleeve ing completelyclosed off by said s eal `fromfsaid'lower end, "said'fuse havtlie fuseblows` and said sleeve havingopcn vents directly communicating "withlthe at- 10. combination a cylindrical sleeve, an upper stationarycontact mounted in 4said sleeve, a lower stationary contact. mounted in'said sleevef afcylindrical closedA fuse having terminals thereupon, saidfuse being moved into conducting relation with said 'stationary'ternnalsby inserting the same axially;l into: said sleeve, `s aid'lovverstationary terminal being of `greater diameter than said" upper'terminal, sald4 fuse having means for; opening one 'end thereof when thefuse,

" ,blowj s,1iand said sleeve 4having open vents tionaiyt contact's, acylindricalfuse inserted- -tactsln `said sleevejs'aid sleeve having" anexplosion chamber thereirrabovesaid'npper staaxiany-'insaid sleeve and tpara thereof lying Within each of` said contacts, said mak-. ing contactwith saidas'tati'onary contacts, at mounting' block secured to sald.`fuse, a handle 's ecured to saidA mountingV block and mennavvithi'n mymovement of. 'sand Contact.

directlylcommunic'ating' with said end of the Petticoat.

E sleeve for preventing fuse, said 'means c'omprlsing 'a bayonet 'slotlying Wholly within said sleeve and a pin mounted on `said mountingbllock, said pin. being adapted #to` enter said sot. f

12. In combination a cylindrical sleeve, a pair of spacedstationary'contacts in said sleeve, a cylindrical fuse `1oin1ng saidcon,

tacts, a petticoat coverfor the top of said sleeve and a petticoat coverfor the bottom of said sleeve, and flexible connecting leads passingIunder said petticoats vand secured Aconductively to said stationarycontactsr said sleeve having a vent or vents communieating with theatmosphere under` said upper l'pettc'ont, said fuse being' adapted toblow outfat one end and discharge through said vent,

pair of stationary annular contacts mounted in said sleeve, saidcontacts vbein apart, a cylindrical fuse fitting into and connectingsaid contacts, said fuse being mounted axially of saidsl'eeve, saidsleeve having an laperture or vent adjacent the upper end thereof, a cavclosing 'the top of said sleeve., said cap'liaving a cylindricalpetticoat over said aperture, a ieXible stranded conductor passingbeneath petticoat and 'through ,said aperturelan'd connected to 'said rupper stationary annular 1.3Lv In combinationa cylindrical sleeve, ai

spaced 14.*In combination a cylindrical sleeve, i,

' having a pair of 4annular contacts mounted therein andfitting withinvthe side walls of said sleeve, said contacts being s aced apart, acylindrical fuse fitting lnto lan "connectmg sa1d'jcontacts, an apertureor vent adjacent the top of said sleeve, a cap for closing' the top-ofsaid sleeve, said cap havingta petticoat over saidapertureysaid sleevehaving .sightopenings therethrough adjacentthe top of saidl fuse, saidfuse being adapted to blow out of one 'end thereof Iand to give anindication of the same. y

15. In# combination a cylindrical sleeve', having a pair of stationaryannularcontacts 1nounted therein and fit"ti`t'xg` around the insidewalls of said sleeve, a cylindrical.

use .fitting into and connecting sadscontacite, a petticoat securedtothe lower end, ,of said sleeve and having a cylindrical portionextending below the same, a flexible stranded conductor connected tosaidlower stationary` contact and passing under said 16. In combinationa` cylindrical sleeve yizo " having av pair.of-stationaryfv open annularcontacts mounted therein and fitting against 1 -fuse' ,being adapted toih e' insertediintc sleeve', saidilatter sleeve :having a cylindritheside Walls Vof said `sleeve ,a cylindriy f 'cal fuse `connecting saidlcontactfs, said both-. of `said annular contacts, -a1noi1`nting-4locksecured Ito -said ined-an enlargedsleeve. secured ltoi the .lowerl:end ci ,lfsaidl Y*first "tions'on the ends thereof, a mounting b ocksecured to said fuse, a handle secured to said mounting block, a metalplate havin a bayonet slot, said plate lying wholly wiiin said sleeve,and a pin on said mounting block, coperating with said slot to hol saidblock and fuse within the sleeve.

18. In combination a cylindrical sleeve member, a pair of spacedstationary open annular contacts mounted on the walls ofA said sleevemember, a fuse having cylindrical terminal -portions adapted to coperatewith said stationary contacts, a' mounting blockse'cured to lsaid fuse,a bayonet slot in said sleeve member and a pin secured to said mountingblock, said fuse being organized .to discharge the gases of the arcaxially from .erregend thereof.

'19. In combination an external4 insulating supporting sleeve having apair of open annular contacts mounted on the .inner walls thereof, acylindrical fuse member having metallic ferrules forming contacts on theends thereof, the upp'er ferrules being'of greater length than theloweli ferrules, said fuse being organized to discharge the ases of thearcv axially from theupper end t ereof, means comprising a handle forinserting said fuse axially into said annular contacts and means forholding said fuse and han dle against "outward movement after said fusehas engaged the upper contact, and beioreithas engaged the lowercontact, said means comprising a double bayonet slot and a 'pin movableinto and out of saidtslot.

20. In combination a cylindrical fuse member organized to discharge thegases of the arc 'axially from one end thereof, a cylindrical mountingblock coperating with screw threaded parts for securing saidafusememberandfsaid yblock in axial alinement,

and ai sleeve member inclosing said "fuse ,member and said block, saidblock and said sleeve,haf'vivlg coperating locking means for holding.the parts together, said locking meanscomprising a double bayonet slotyand a pm.l l

Y 21. In combination a cylindrical sleeve member, having stationaryannular contacts therein, a cylindrical fuse member having terminalportions adapted to coperate wlth vsaid, stationary contacts, said fusemember "beingorgamzed to discharge the gases of thev arc axially fromoneend thereof, a mounting yblock secured to said vconnectingmember andvcinterlocking 'parts on said' mounting' block-and said sleeve memberfor securing said Im'rts together, lsaid partscomprising a doublebayonet slot and a pin movable in from' one end thereof, a mountingblock forv supporting the fuse, a slot in said sleeve member, said slotcomprising two vertical portions and two horizontal portions and a pinon said mounting block coperating with said slot.

23. In combination a sleeve member having stationary annular contactstherein 1ying against the walls of the sleeve, said contacts beingspaced apart, a fuse for connecting said contacts, said fuse beingorganized to discharge the gases of the arc Vaxially from one endthereof, a mounting block secured to said connecting member, said sleevemember having a slot therein and said mounting block having acooperating pin, said slot comprisingl two vertical and two horizontalportions.

24. Incombination a cylindrical sleev member, having stationary contactstherein, a cylindrical connecting member having contact portionsengaging said stationary contacts, a mounting block secured to saidconnecting member, said sleeve member having a petticoat surroundingsaid mounting block below said statlonary contact, said mounting blockhaving petticoated insulat-v ingmeans secured thereto below said petti-26. In combination a cylindricalY sleeveA member, an annular stationarycontact. .member mountedadj acentthe lower end thereof, a, stationarycontact member adjacent the upper end thereof, a cylindrical fuse means'adapted. to be inserted' axially and lie Within said stationary contactmember for connect-- 111g th same, resistance means connected to thelower end of said. fuse and'means for moving said fuse axially -intosaid ationary annular contact and against'said upper stationary contactwhereby the lower stationary "annular contact member is brought intocontionary tactwith the resistance means in series with the fuse. v

27. In. combination a sleeve member, a stationary contact mounted in theupper end thereof, a contact member mounted in the lower end thereof, acylindrical fuse member havingte'rminals adjacent the ends thereof, saidterminals connecting with said stationary contacts, resistance meansconnected to said lower terminal, and means i'orbrin,f ,1ing

one end of said resistance 1n contact with said lower contact after theupper end of said fuse means engages said upper contact means and beforethe lower tern'linal engages the lower stationary contact.

28. In combination a cylindrical conductq ing member having a metalferrule adjacent the end thereof. said ferrule having its end fared ntl'normal to its axis, a threaded stud secured thereto, a mounting blockhaving a threaded socket for receiving saidV stud, and a spring washerbetween said ferrulc and lsaid mounting block, said mounting block haring its top surface faced ofi' norlnal to its axis to abut against theend of the fuse ferrnle and haring a circular recess for said springwasher.

2E). In combination a cylindrical sleeve of insulation, a pair of spacedstationary contacts in said sleeve, a fuse connecting' said contacts,said inse comprising a glass tube having metal fer-rules for connectingsaid spaced stationary contacts, Said sleeve having diametricallyopposite apertures therethrough, said fuse having an element normallylying in line with said aperture to obstruct the passage of lighttherethrough and adapted to be moved ont of said line upon blowing ofthe fuse and means for closing said diametrieally opposite apertures.

30. In combination a vertical sleeve of insulation, a pair of annularcontacts lying against the walls of said sleeve upon the interiorthereof, said walls having diametrical apertures therethroughintermediate said annular contacts, a band having apertures adapted tobe brought into register with the apertures in said sleeve and acylindrical fuse adapted to be inserted axially into said annularcontacts to connect the same, said fuse having a portion normally lyingin line with said apertures and adapted to be removed when the fuse isblown so4 as to give a clear view for the transmission of light throughsaid apertures.

31. lnl combination a cylindric:1 sleeve member having stationarycontacts cured therein, a cylindrical fuse member having terminalsadapted to engage said stationary contacts, resistance means connectedto one of said terminals, said resistance means being adapted to engageone of said statiow ary contacts and to be placed in circuit in serieswith said fuse member upon moving said fuse out of said sleeve member tocause the circuit to be broken at said resistance llllllls.

. In witness whereof, I hereunto subscribe inv name this 13th day ofOctober, A. D.

NICHOLAS J. CONRAD.

